Spring hinge construction for bulkhead doors



Nov. 11, 1 5 B. P. STEARNS ETAL SPRING HINGE CONSTRUCTION FOR BULKHEAD DOORS Filed June 6, 1950 m mm 58 ST Y E N A M N c 0 E l I T mmi y M T mm H" Um l Patented Nov. 11 1952 SPRING HINGE CONSTRUCTION FOR BULKHEAD DOORS Benedict P. Stearns and Ernest .J.-Carls 0n, 'Wo'r'cester, Mass.

Application .June'6, 1950, Serial No. 1'66,317 1 Claim. (Cl. 16 135) This invention relatestolimprovements in bulk-- head or cellar doors, of the type that giveaccess from out-of-doors to a hatchway or stairway leading to the basement of abuilding.

Objects of the invention are to simplify the construction and assembly-of such devicesand in particular to provide, in connection with the hinging of the door,a-spring action whichis effective, on the opening movement of the door, to counterbalance the latters weight, and which also holds the door, when closed, tightly and firmly seated on its casing or frame.

Other and further objects and advantages of the invention will "be made apparent in the following detailed description thereof taken in connection with the accompanyingsdrawings in which Fig. 1 is a, perspective view, showing the bulkhead door of our invention'in its open-position.

Figs. 2 and 3 are fragmentary larger scale sectional views, illustrating thespring action in the open and closedposition, respectively, of the door.

Like reference characters refer to flike parts in the different figures.

In the illustrated embodiment of our invention, the door I and its casing or frame are preferably constructed of sheet metal. These parts are of substantially conventional form throughout, the casing being constructed to fit over and to box in the usual rectangular ground level cellar-opening. That is to say, said casing has the customary upright side walls 2, 2 which are triangular in shape, so as to give the casings top or cover the usual downward slope, outwardly from the building wall. Said sloping top or cover comprises side panels 3, 3, and a connecting upper panel 4, the side panels at their outer edges being suitably connected with the sloping upper edges of the respective triangular walls 2, 2, and the upper panel 4 having a flange 5 by which to obtain, in any usual way, a substantially watertight connection with the building wall. The cover panels 3, 3 and 4 thus provide three sides of a rectangular casing opening that gives access to the boxed-in hatchway, the fourth side of such opening being substantially at ground level and being provided by a suitable plate 6 connecting the outer ends of the casing sides 2, 2. Suitable bolt holes in said plate 6, and also in angle bars 7, 1 welded along the bottom edges of the casing sides 2, 2 may be provided, for attachment of the casing to the masonry or the sills, as the case may be, which surround the cellar-opening, and similar bolt holes for attachment of the casing to the building wall, may be provided in the flange 5. The casing at its doors edges are :preferably down turned, as

shown at 9 9, and are adapted, in the doors closed position, to lie "outside of the upturned edges 10, 1160f side panels 2, 2 ;and the upturned edge ll of upper panel 4. For the ,hinging of said door, each channel iron 8 near its upperend has alined apertures in its sides to receive-a horizontal pivot pin l2, the two -pi-vot :pins :being in alinement with each other. IIhe door 4 on ,its .under surface has a transverse reinforcement into the respectivechannels 8, 8, .a .pair of verticallydi$pQsed brackets .or plates rIll, .13. .Each plate 14 has an upturned arm [5 which is apertured to receive one of the pins l2, thereby to provide a pair of hinges for the door to swing on, in moving from the closed position of Fig. 3 to the open position of Fig. 2, and vice versa. Our improved spring action, by which the door, de spite its weight, can be raised, substantially without effort, to its open position, is applied to and has the same construction for both of the abovedescribed hinges; hence a description of one of such spring actions will suffice for both.

As shown in Figs. 2 and 3, each hinge plate [4, substantially at the base of its upturned arm I5, is apertured for passage of a pin I6, the latter serving for the pivotal connection to said plate of a depending threaded rod ll, whose lower end, as best shown in Figs. 2 and 3, is telescopically received in a tubular member l8. Extending diametrically through member I8 near the lower end thereof is a pin l9, whose oppositely projecting portions provide a seat or abutment for the lower end of a compression spring 20, surrounding the member is and extending past the latters upper end, so as to bear against a washer 2i encircling the threaded rod l7, beneath an 8. Said plate 23 has an opening 24, large enough to receive, loosely and rockably, the end portion of the tubular member l8 that lies beyond and below the pin I9. In this way, the above described spring action assembly is seated on the plate 23, in such manner as to have freedom for rocking movement, with pin l9 serving as a trunnion, when the door I is moved from open to closed position and vice versa.

In the doors movement to closed position, not only are both springs 20, 20 put under compression, but also, as shown in Fig. 3, the spring action assemblies are swung over'to a substantially vertical position, with each pivot pin [6 preferably moved by the doors weight, to a point just beyond a line 25 connecting the hinge axis l2 and the trunnion axis i9. Under these conditions, the compressed springs are effective through a small leverage to keep the door tightly closed. However, the initial effect of an upward manual pull on the door is to shift each pivot pin 16 to the other side of line 25, whereupon the storedup force of both springs 29, 29 is at once applied, with constantly increasing leverage, to the movement of door l to its full open position, as shown in Figs. 1 and 2. In other words, as soon as the closed door I is manually swung upwardly through a very smallarc, the springs 20, 29 take over, in whole or in part, the work of raising the door, by an expanding action which, as shown in Fig. 2, forces each rod l1 upwardly, relative to the tubular member [8 in which it is slidably telescoped. Initially, when the compressed springs expansive force is at its maximum, the leverage is small, but such leverage increases rapidly as the pivotal connection 16 swings more and more to the left (Figs. 2 and 3) thereby to compensate for the springs gradually decreasing expansive force. 7

We claim:

A spring hinge construction for the cover or door of a. bulkhead or hatchway, comprising a channel member adapted to be secured in substantially upright position within said bulkhead, a bracket adapted to besecured to said door and projecting into the upper end of said channel member, a pivot pin passing horizontally through said bracket and the sides of said channel member to provide a hinge at said channel members upper end for the swinging movements of said door, a plate secured across the lower end of said channel member and having an aperture whose axis is alined substantially with a perpendicular line from the axis of said pivot pin, a tubular member loosely received at its lower end in said plate aperture, a pin extending transversely through said tubular member and seating on said plate, to provide-a trunnion support. substantially parallel with said pivot pin axis for the swinging movement of said tubular member, a threaded rod having a pivotal connection at its upper end with said bracket, in offset relation to said pivot pin axis, said rods lower end being telescopically slidable in said tubular member, an adjusting nut threaded onto said rod, and an expansion spring surrounding said telescoped parts and confined between said nut and said plate so as to be put under compression by closing movement of said door, said springs force being eifective for the opening movement of the door when said pivotal connection lies at one side of said perpendicular line, and being eifective to hold said door'closed when said pivotal connection moves to the other side of said perpendicular line.

BENEDICT P. STEARNS. ERNEST J. CARLSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATIENTS 

